The present invention relates to electrically operated valves controlled in response to an electric signal, and more particularly to an electrothermally operated valve including a bimetallic element to be heated by a heating coil to control the operation of the valve.
In a conventional electromagnetically operated valve, expensive copper wires are used to obtain high response characteristics, and semiconductor elements, such as a switching transistor and the like, are assembled to control the operation of the valve. In practical use the semiconductor elements are occasionally damaged due to a high surge voltage induced upon energization or deenergization of the solenoid windings.